Regenerative heat exchanger



March 19, 1968 AKE NYBERG,

REGENERATIVE HEAT EXCHANGER Filed Nov. 29, 1966 INVENTOR. AKe Lcnnaat Nbenq I'BY w I a a,

United States Patent 3,373,797 REGENERATIVE HEAT EXCHANGER Ake LennartNyberg, Nacka, Sweden, assignor to Svenska Rotor Maskiner Aktiebolag,Nacka, Sweden, a corporation of Sweden Filed Nov. 29, 1966, Ser. No.597,586 Claims priority, application Great Britain, Nov. 29, 1965,50,526/ 65 Claims. (Cl. 165-9) ABSTRACT OF THE DISCLOSURE Apparatus foruse with rotary regenerative heat exchangers having sector plates andaxial sealing means which provides for sudden thermal deformations ofthe rotor which can cause jamming between the adjacent surfaces of therotor, the sealing means and the sector plates by providing a singleyielding connection interconnecting the sector plates and the adjacentsealing means at each end of the rotor which transmits motion betweenthe sector plates and the adjacent sealing means so that the movement ofthe latter in response to a deformation brings about a correspondingmovement of the former, thus avoiding contact between the two.

The present invention relates to a regenerative heat exchanger of thetype which comprises a stationary housing in which is provided acylindrical rotor containing a regenerative mass. The housing includesducts for the heat exchanging fluids and these ducts have openings ateither end of the rotor for directing separate flows of fluid throughthe regenerative mass. In order (it prevent mingling of the fluid flowsthere are provided sealing means between the rotor and the housing whichinclude swingable sector plates hinged at their radial inner ends to thestationary housing and located in sealing proximity to the end surfacesof the rotor for separating adjacent duct openings, each sector plate atone end of the rotor being axially aligned with a sector plate at theopposite end. Further there are provided axial sealing means extendingbetween aligned sector plates and cooperating with the outer cylindricalrotor surface.

In heat exchangers of this type the rotor is subject to thermaldeformation during operation due to non-uniform temperaturedistribution. For the same reason also the housing is deformed to acertain degree. In normal operation the swingable sector plates adaptthemselves to the dished form of the rotor and the axial sealing meansmay be adjusted to occupy the correct position relatively to the outerrotor surface.

Under certain conditions such as at start and over-load the deformationsmay be so large as to cause jamming of the rotor due to contact betweenthe rotor and the sector plates and axial sealing means respectively.The sector plates and the axial sealing means are actutaed by meansyieldingly forcing them towards stop members determining their operativepositions. In this manner jamming of the rotor is prevented as thesector plates and/or the axial sealing means move away against theaction of the yielding force when they come into contact with the rotorso that this contact only results in a certain braking of the rotor butnot in a total stand-still. This braking action in turn results in agreater power demand indicated by a suitable instrument or alarm deviceso that the positions of the sector plates and/or the axial. sealingmeans may be manually adjusted.

According to the invention there are provided motion transmitting meansinterconnecting the sector plates and the axial sealing means such thatan increase of the distance between the outer ends of aligned sectorplates refrom the position shown.

3,373,797 Patented Mar. 19, 1968 sults in a radial outward movement ofthe adjacent axial sealing means. Thanks to this connection it ispossible to use a single common means for producing the yielding forceacting upon the sector plates and the axial sealing means. Further, iffor instance the conditions are such that due to the thermal deformationof the rotor its cylindrical surface comes in contact with the axialsealing means and moves it outwardly the sector plates are somewhatseparated so that they do not come in contact with the end surfaces ofthe rotor. Under other conditions the deformation of the rotor may causeseparation of the sector plates in which case the axial sealing means ismoved outwardly so that it does not come in contact with the rotor. Itis evident that in this manner the rotor will be braked either by theaxial sealing means or by the sector plates but practically never by theaxial sealing means and the sector plates at the same time.

In the accompanying drawing there is shown a perspective view of a partof regenerative heat exchanger according to the present invention.

The drawing illustrates the invention as applied to a heat exchanger ofthe type shown in our US. Patent No. 3,250,316, granted May 10, 1966 andmore particularly to such a heat exchanger provided with a deviceaccording to FIG. 14 of said patent application.

Referring to the drawing reference numeral 10 indicates a cylindricalrotor which is divided into sectorial compartments by partitions 12. Therotor 10 is rotatably mounted in a housing 14 which is provided withducts for the heat exchanging fluids parts of which are shown in brokenlines in the drawing at 16 and 18.

In circumferential direction the openings of the ducts 16 and 18 are inknownmanner separated by sector-shaped plates two sector plates beingprovided at each end of the rotor and each sector plate at one end ofthe rotor being in axial alignment with a sector plate at the other endof the rotor. In the drawing there are shown two axially aligned sectorplates viz. an upper sector plate 20 and a lower sector plate 22'. Attheir radially inner ends the sector plates 20 and 22 are hinged tostationary center plates (not shown) so that they are swingable in anaxial plane.

A rod 24 is secured to the lower sector plate 22 and extends upwardlythrough a tubular member 26 secured to the' upper sect'or plate 20 andpassing freely through a stationary casing end wall 28. On a threadedportion of the rod 24 there is provided at the under side of the sectorplate 20 a nut (not shown) which serves as an adjustable stop memberdetermining the minimum distance between the ends of the sector plates20 and 22.

A link 30 is pivotally connected to the housing end wall 28 and supportsa lever 32 one arm of said lever 32 carrying a weight 34. The other armof the lever 32 is pivotally connected to a suspension lever 36 which isprovided with a plurality of holes for the suspension of the rod 24. Inthe example illustrated the upper end of the rod 24 is connected to ahole located vertically below the pivotal connection between the lever32 and the suspension lever 36.

One end of the suspension lever 36 is inserted between an eccentric 38and a stop member 40 carried by a bracket 42 secured to the tubularmember 26, The eccentric 38 and the stop member 40 are located such thatthey prevent counterclockwise swingin g of the suspensionlever 36 Toeach sector plate is secured a radially outwardly extending bar 44 ontowhich is threaded a tube 46. Each tube 46 carries a yoke member 48' theends of which are connected to a frame-like link element 50 which inturn is connected to an axially extending sealing member 52 cooperatingwith the outer cylindrical surface of the rotor 10. The link elements 50form an angle of about 45 with the axis of rotation and converge towardsthis axis.

The ends of the bars 44 and the tubes 46 protrude through holes in thehousing 14 which holes are such as to permit a certain axial movement ofthe bars and the tubes. Each tube end is threaded and carries a nut 54which is rotatably connected to the end of the bar 44. It is evidentthat turning of the nut 54 will result in a radial movement of the yoke48.

The holes in the housing 14 are surrounded by bellows-like seals 56.

Each link element 50 carries an axially directed lever member 58. At thefree end of one of the lever members 58 there is provided a pin 60 whichengages a slot 62 at the end of the other lever member 58, The levers 58form a coupling means between the link elements 50 so that theseelements swing substantially synchronously in opposite directions.

The axial sealing member 52 is substantially U-shaped in cross sectionand its substantially radial side-portions cooperate with radial walls64 secured to the inside of the housing 14 in order to prevent minglingof the fluid flows in the space between the rotor and the housing 14.

The weight 34 forms a counter-weight which counterbalances the weight ofthe sector plates and 22, the axial sealing means 52 and all partscarried by these elements. Therefore, a very little force is required toswing the whole system so that a normal deformation of the rotor ispossible without any risk of harmful contact pressure between the rotorand the sector plates and axial sealing means respectively. However, thecounter-weight 34 also produces a force biasing the sector platestowards each other and towards the position determined by theabove-mentioned stop member provided on the rod 24. Due to the linkelements 50 this stop member also determines the position of the axialsealing member 52.

It is evident that a radial outward movement of the axial sealing member52 will be yieldingly counter-acted by the force exerted by thecounter-weight 34 and the movement will take place under a simultaneousseparation of the sector plates 20 and 22. correspondingly a separationof the sector plates 20 and 22 will be yieldingly counter-acted by thecounter-weight 34 and will take place under a simultaneous radialoutward movement of the axial sealing member 52.

By means of the nuts 54 the position of the axial sealin-g member 52 maybe adjusted such that there is always a desired small clearance ofuniform width also when the outer surface of the rotor becomes slightlyconical. By turning one of the nuts 54 it is possible to vary theinclination of the sealing member 52 and by turning both.

nuts 54 the radial position of the member 52 is varied. Theseadjustments do not affect the sector plates 20 and 22. However, if thesealing member 52 is subjected to a radially outwardly directed force itmoves outwardly in the same manner irrespective of the position of thepoint where the force is applied and this movement results in aseparation of the sector plates. Due to the coupling means formed by thelever members 58 a radial movement of the upper end of the sealingmember 52 is always accompanied by a corresponding movement of the lowerend thereof.

Due to the fact that the link elements 50 form an angle of about 45 withthe axis of the rotor the force opposing outward movement of the sealingmember 52 will be substantially the same as the force opposingseparation of the sector plates 20 and 22.

In order to permit manual separation of the sector plates 20 and 22 anda corresponding retraction of the axial sealing member 52 the eccentric38 is provided with a handle 39 by means of which the eccentric 38 canbe turned such that the suspension lever 36 is swung clockwise wherebythe sector plates are separated.

The housing 14 is provided with suitable openings through which the stopmembers on the rods 24 are accessible for adjustment.

By selecting different holes of the suspension lever 36 for theconnection of the rod 24 it is possible to vary the force exerted by thecounter-weight 34 and biassing the sector plates towards each other andthe sealing member 52 towards the rotor.

The invention is not limited to embodiments of heat exchangers in whichthe force biassing the sealing elements towards their operativepositions are produced by weights but may be applied also to suchexchangers in which the said biassing force is exerted by springs.

I claim:

1. A regenerative heat exchanger comprising a stationary housing, acylindrical rotor provided in said housing and containing a regenerativemass, said housing including ducts for the heat exchanging fiiuds andsaid ducts having openings at either end of said rotor for directingseparate flows of fluid through said regenerative mass, sealing meansbetween said rotor and said housing for preventing mingling of the fluidflows, said sealing means including swingable sector plates hinged attheir radially inner ends to the stationary housing and located insealing proximity to the end surfaces of the rotor for separatingadjacent duct openings, each sector plate at one end of the rotor beingaxially aligned with a sector plate at the opposite end, and axialsealing means extending between aligned sector plates and cooperatingwith the outer cylindrical rotor surface, and motion transmitting meansinterconnecting said sector plates and said axial sealing means suchthat an increase of the distance between the outer ends of alignedsector plates results in a radial outward movement of the adjacent axialsealing means.

2. A heat exchanger as defined in claim 1 in which said motiontransmitting means consists of a linkage comprising link membersconnecting each sector plate with the adjacent axial sealing means, saidlink members being swingable in substantially axial planes andconverging towards the axis of rotation.

3. A heat exchanger as defined in claim 2 in which said linkagecomprises adjustable articulation points.

4. A heat exchanger as defined in claim 3 in which the connection pointsof said links to said sector plates are radially adjustable.

5. A heat exchanger as defined in claim 2 and further comprisingcoupling means operatively interconnecting corresponding links at eitherend of the rotor such as to make these links swing substantiallysynchronously in opposite directions.

6. A heat exchanger as defined in claim 5 in which said coupling meansincludes two lever members each being rigidl secured at one end to oneof the links to swing therewith, the free ends of said lever membersbeing pivotably and slidably connected in order to transmit swingingmotion from one link to the other.

7. A heat exchanger as defined in claim 1 and further comprising meansyieldingly forcing said sector plates towards each other and a stopmember determining the smallest distance between the outer ends of saidsector plates.

8. A heat exchanger as defined in claim 2 wherein each link forms anangle of about 45 with the axis of rotation in the normal workingposition of the sector plates and axial sealing means.

9. A heat exchanger as defined in claim 7 comprising: means for manualseparation of said sector plates.

10. A heat exchanger as defined in claim 7 comprising. meansinterconnecting the outer ends of said axially aligned sector plates,said means comprising a lever system including a suspension lever, afirst element carried by the upper one of said sector plates and asecond element carried by the lower one of said sector plates, said twoelements being attached to two horizontally spaced,

points on said suspension lever, a substantially horizontal double armlever swingably mounted on a stationary support, a counter-Weightsecured to one arm of said doublearmed lever, the other arm of saiddouble-armed lever being pivotally connected to said suspension leversuch as to exert a force on said suspension lever tending to move saidsector plates towards each other While said counter-weightcounterbalances the Weight of the sector plates and associated movableparts.

References Cited UNITED STATES PATENTS 2,873,952 2/1959 Mudersbach et a11659 3,246,687 4/1966- Jensen et al. 1659 3,250,316 5/1966 Nyberg 165-9EDWARD J. MICHAEL, Primary Examiner.

A. W. DAVIS, JR., Assistant Examiner.

